Sec Form 4 Filing - WOLFE ROBERT A @ GENCORP INC - 2004-12-31

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person WOLFE ROBERT A 2. Issuer Name and Ticker or Trading Symbol GENCORP INC [ GY] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) HIGHWAY 50 & AEROJET ROAD 3. Date of Earliest Transaction (MM/DD/YY) 12/31/2004 (Street) RANCHO CORDOVA, CA95670 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 12/31/2004 D( 1 ) 500 D $ 0 ( 2 ) 190,042.4506 ( 3 ) D Common Stock 11,929.8493 ( 4 ) I Plan Trust

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other WOLFE ROBERT A HIGHWAY 50 & AEROJET ROAD RANCHO CORDOVA, CA95670 X Signatures Mark A. Whitney as Attorney-in-Fact 01/03/2005 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Restricted stock forfeited due to Mr. Wolfe's resignation before the vesting of these shares. ( 3 )This footnote explains an exempt transaction which is not reportable, yet the addition of those shares must be recognized in the total shares. In this case the common stock balance has been updated with 501.4892 shares acquired on 5/28/04 under the GenCorp Dividend Reinvestment Program. ( 4 )This footnote explains an exempt transaction which is not reportable, yet the addition of those shares must be recognized in the total shares. In this case, shares held in the GenCorp Retirement Savings Plan Trust (Plan Trust) have been adjusted downward by 2,227.0995 shares as of December 20, 2004 to reflect the value in the participant's account as per the Plan Administrator's records. The number of shares reported is calculated by dividing the dollar value of the participant's account by the closing stock price printed in the New York Stock Exchange Composite Transactions in the Wall Street Journal on the day reported above. This calculation yields only the approximate number of shares in the participant's account because the cash component in the Plan Trust (target 2%) is allocated to each participant's account on a pro rata basis, and the cash component varies based on overall activity of all participants in the Plan Trust. ( 2 )Due to the nature of the transaction, the Price of the Non-Derivative Security is not relevant to the transaction.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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